The present invention relates to a reversible chain or caterpillar tractor for buffering elongated stock, such as tubes or pipes.
Caterpillar tractors or traction type conveyors are known having a sprocket type drive wheel for the traction chain and being arranged at one end, while a reversing wheel with tension equipment is provided on the opposite end. These known tractors are disadvanted by the fact that the chain traction force is increased by the tension device. This is a direct and inevitable consequence of the known arrangement. Moreover, an arrangement of the drive system in the range of the delivery facilities of the tractor impedes utilization of rotating delivery and transfer operations. A gapless transition between chainwheel and chain support is not possible for reducing the backing length for the stock to be buffered. Upon tensioning or retensioning the chain, the distance between the axles of the chainwheel is changed.